For most of the world's population, the production of crops (as opposed to livestock foods) provides the bulk of dietary intake. Global production of the staple (most important) food crops has increased over the last 10 years--but so has global population. In Africa, for example, despite a 30 percent increase in staple crop production since 1981, per capita food output has dropped more than 5 percent because of population growth that is faster than the growth in agricultural output. The map illustrates considerable regional differences in outputs of food staples per areal unit of cropland. On a global average, 1 hectare (2.47 acres) of cropland in 1990 yielded about 2.6 metric tons (2,600 kilograms, or about 5,700 pounds) of cereals or about 11.8 metric tons of roots and tubers. Yet in Africa, 1 hectare yielded only 1.2 metric tons of cereals or 7.9 metric tons of roots and tubers. In Europe, by contrast, 1 hectare yielded 4.2 and 21.2 metric tons of cereals or roots and tubers, respectively. Such great differences are explainable primarily in terms of agricultural inputs: different farming methodologies, varying levels of fertilizers, agricultural chemicals, irrigation, and machinery. The European farmer applies 2.3 times more fertilizer per hectare than the global average, the African farmer only one-fifth of the global average. These conditions are not likely to change, and the map may be viewed not just as an indicator of present agricultural output but of potential food production as well.